Answer:
The answer is Tonya's phone had the greater initial trade-in value.
Leo's phone decreases at an average rate slower than the trade in value of Tonya's phone.
Explanation:
Given
Tonya
Leo
Solving (a): The phone with greater initial value
The initial value is when x = 0. So, we have:
From Leo's table
By comparison;
i.e.
So: Tonya's had the greater initial trade-in value
Solving (b): The phone with lesser rate
An exponential function is:
Where:
For Tonya
For Leo, we have:
So, the equation becomes:
and
Solving
, we have:
becomes
Divide both sides by 480
Take square roots
-- Leo's rate
By comparison; Leo's rate is slower i.e. 0.87 < 0.88